Last month, the five-day average of Antarctic sea ice passed 20 million square kilometers. It was the first time that has happened since 1979 according to the National Snow and Ice Data Center.
See the red line in the image above? That’s the average maximum ice pack from 1979-2014.
What does this mean in terms of global warming?
“The planet as a whole is doing what was expected in terms of warming. Sea ice as a whole is decreasing as expected, but just like with global warming, not every location with sea ice will have a downward trend in ice extend,” says Claire Parkinson, a senior scientist at NASA’s Goddard Space Flight Center.
In fact, Arctic sea ice loss is offsetting growth in the Antarctica by about 3 to 1.
According to the NASA report, the Arctic has lost, on average, about 20,800 square miles of ice a year since the late 1970s. In the same time span, the Antarctica has gained 7,300 square miles of ice, on average.
Check out the video below to see a side-by-side look at the growth in ice in the Antarctic and the loss in the Arctic.
One possible explanation is changing weather patterns that are affecting winds in the area. For example, a low-pressure system in the area could change wind patterns and push cold air from the Antarctic continent towards the Ross Sea, which is seeing the biggest ice growth.
“The winds really play a big role,” Walt Meier, a research scientist at Goddard, said.
While the winds could play a substantial role, it can’t be the only reason for the new record maximum ice pack according to Meier. Other factors including water circulation patterns and even snowfall could be responsible.
“Its really not surprising to people in the climate field that not every location on the face of Earth is acting as expected – it would be amazing if everything did,” Parkinson added.
“The Antarctic sea ice is one of those areas where things have not gone entirely as expected. So it’s natural for scientists to ask, ‘OK, this isn’t what we expected, now how can we explain it?’”
Joey Comiso, also with NASA’s Goddard Center, talked more about the possible reasons for the rising Antarctic sea ice in a Q&A.